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The River is the reason that the City of Los Angeles was established where it is.

The River was the City’s main source of water supply until 1914.

The River is home to over 250 species of birds.

The River was once a prime habitat for Grizzly Bears.

The last photo of a native Steelhead Trout caught in the River was in the late 1940s.

Water quality in the living sections of the River is markedly better than in its concrete stretches.

It took 30 years and 3.5 million barrels of concrete to channelize the River.

In 1995, it was designated the country’s Most Threatened and Endangered River.

Prior to channelization, 215,000 acres were subject to flooding.After channelization and subsequent development, 325,000 acres were at risk. Over 60% of our urban landscape is paved.

Urbanization has greatly altered the rivers’ natural flow and the functioning of our watershed. 100 years ago, as much as 80% of rainwater could percolate into the ground Now as little as 10% of rainwater percolates into the ground, with the rest draining out to sea. An acre of parking lot produces 1600% more runoff than an acre of green space.

In times of peak flow, the river carries as much water as of 80 million garden hoses going full blast per second out to the Pacific Ocean – 14 times the flow of NY’s Hudson River.

An acre-foot of water is the amount of water it takes to cover a football field to 1’ deep. An acre-foot of local groundwater used for drinking water costs about $200 An acre-foot of imported MWD drinking water costs about $800 (and rising) An acre-foot of Evian cost about $3 Million Each 1” storm creates 24,000 acre-feet of run-off, costing us ~$19 Million. The San Fernando Valley Groundwater Basin has 505,000 acre-feet of available storage space.

THIS IS NOT A DESERT!! We live in a Mediterranean climate zone characterized by wet winters and long dry summers. The Mediterranean ecosystem exists on only 3% of the earth’s land surface, and worldwide, is more threatened than the rainforest. Our ecosystem is one of the world’s top ten "hotspots" of biodiversity.

More than 30 federal, state and local agencies are involved the Los Angeles River.